CustomHeaders issues, filter URL parameter no longer working!

Hi,

I'm facing same issue with 2 customers.

I recently upgrade two differents Power BI Report Server from october 2019 to latest version, february, 12 2021.

I have a lot of Power BI embeded reports that were working fine before this upgrade. The Web front end portal is outside our domain.

After upgrade, I read some other users posts about CustomHeaders settings in advanced options (SSMS, report server, etc..)

My current CustomHeaders settings is:

<CustomHeaders><Header><Name>X-Frame-Options</Name><Pattern>(?(?=.*api.*|.*rs:embed=true.*|.*rc:toolbar=false.*)(^((?!(.+)((\/api)|(\/(.+)(rs:embed=true|rc:toolbar=false)))).*$))|(^(?!(http|https):\/\/([^\/]+)\/powerbi.*$)))</Pattern><Value></Value></Header></CustomHeaders>

Now I can only see the embeded report if I remove the "filter=..." URL parameter.  

Filter is very simple:
?filter=Product/Familly eq 'Computer'

theres' no space, no special char, char case is correct.

Seems the new CustomHeaders options does not support "filter".
Is there a fix?

I can confirm it's a BUG because when I restore ReportServer databases, install October 2019 version, PBRS security key, all work fine. So, latest version has a BUG with ther "filter=" parameter!
 
Regards,
Denis